Rotary plate-like screen



June 18, 1929. o. wlENcKE ROTARY PLATE LIKE SCREEN Filed June 22, 1928 5 Sheets-Sheet l FLQ- 2- In uen ow June 18, 1929. o. wlENcKE .ROTARY PLATE LIKE SCREEN Filed June 22, 1928 3 Sheets-Sheet 2 Invenvw- June 1s, 1929. o. WIENCKE 1,717,902

ROTARY PLATE LIKE SCREEN Filed June 22, 1928 3 Sheets-Sheet 3 QQR la. j:

Patented June 18, 1929.

UNITED STATES OTTO WIENCKE, OF LEIPZIG, GERMANY.

ROTARY PLATE-LIKE SCREEN.

AppIication filed J'une 22, 1928, Serial No. 287,452, and in Germany December 1, 1926.

The present invention has for its object to provide a rotary plate-like screen for materials to be sifted. A characteristic feature of said rotary-screen consists in that the outer periphery or rim of the plate prot-ruding above the screen-surface is arranged as a belt-pulley provided with a slot or slots situated above the screen-surface. A belt guided on one or more guideor drive-rollers is moved around said belt-pulley in such a manner that the slot or slots of the upwardly protruding periphery or rim are covered by said belt up to the point where the belt is raised from the guideor drive-rollers and the slot or slots are opened for discharging the material of coarser grain which remains on top of the plate-like screen. A practical embodiment of the invention is represented in the accompanying drawings, in which Fig. 1 is a vertical section (through the line I-I of Fig. 2, looking in the direction of the arrows) and Fig. 2 is a top plan of the plate-like screen.

Figs. 3 and 4 show in vertical section and in top plan a modification of the screen and Figs. 5 and 6 show in vertical section and in top plan another modification of the same.

Fig. 7 is a detail end view of the disc arranged with noses or pins.

As clearly seen from Figs. 1 and 2 the rotatable lplate-like screen b is fastened on the driven shaft a and arranged with a periphery or rim c protruding above the screen-surface.

lIn this periphery or rim c a slot or slots d lis or are arrangeddirectly above the screensurface. Said periphery or rim c protrudingl above the screen-surfacek is formed as a belt-pulley around which a belt c is moved, thel latter being guided over a roller f, Fig. 2, in such a manner that the slot d arranged in the periphery or rim c is covered or-closed and is only open at the periphery or rim c,

viz,; from the lpoint of separation of they A--upA belt from the belt-pulley-see point to the point of the belt again touching the pulleysee point B. The material of coarser grain resting on the plate-like screen b and notv siftedthrough is thrown by centrifugal force through the part ofy said slot d not coveredby the belt e and drops into the receiver or vessel g, whereas the material of fine grain is sifted into the collectingvessel 71..

supply of material t9 be sifted to thel plate-like screen Z) is caused by an endless band so arranged that the material is supplied to the screen tangentially and across the width of the sifting-surface. The speed of the endless band c is so proportioned that the speed of the material fallingV onto the sifting-surface is substantially equal to the horizontal speed measured at the radial center of the rotating sifting-surface.

As seen from Figs. 3 and 5, the drivingshaft Z of the plate-like rscreen b can be arranged to slant at a suitable angle to the vertical in order that the material to be sifted may be received from the feed supply band on the one side by a rising screen-surface and discharged into vessels on the other side by the descending surface..

The rotatable plate-like screen can be formed, as shown in Figs. l and 6, by two or more concentrically arranged disc-rings m, m1, suitably secured together and supported from the drive shaft Z.

In case the plate-like screen b is subdivided into several disc-rings, the endless-band 7c can be arranged in such a manner, that the latter is seated above the disc-ring situated nearest to the centre, as represented in Fig. 4 in plan. The speed of thc endless-band ,7c is such thatthe material to be sifted is fed with a speed substantially equal to the horizontal speed in the radial middle of the disc-ring nearest to its centre.

For the purpose of adapting the supplyspeed of the material to be sifted to the surface speed of a plurality of rings, the endless supply-band c can be subdivided, as seen 1n Figs. 5 and 6. The two endless-bands k1, 7a2 are separately driven so that the speed of the material leaving said two endless-bands may Vbe adapted to the surface speeds of the several screen-rings, as before explained.

To ameliorate the sifting-procedure and' to provide a cleansing procedure, the plate-like screen b can I during its rotary movement, be subjected to a vibratory movement. For this purpose there is provided, as shown for 1nstance in Figs. 3 and 5,*a ring-surface o at the lower surface of the plate-like screen, said ring-surface resting on a disc g arrange with noses or pins p (Fig. '7) or on aneccentric disc, so that the plate-like screen is sub- `iected to a vibratory or jarring movement ppon the lrotation of said dlsc.

I As clearly seen in Figs, 3 and 5, the bearings Carrying the staf-Lgf the, pin-dise are yieldingly suspended for the purpose of ensuring a lirm contact of the pin or eccentric disc with the ring.

lVithout in any way leaving the scope of the present invention the disc g can be arranged as a round disc and projections or notches can be arranged cn the ring arranged on the plate-like screen, for the purpose of obtaining a vibratory movement of said screen.

For insuring a better sifting-oii'cct for the material to be sifted and passing through the plate-like screen, the upper surface of said screen can be dished somewhat, as represented in Figs. 3 and 5.

As indicated in Figs. 4f and 6,-the screenapertures t (shaped as slots) are concentrically arranged in the disc-ring m situated towards the middle of the screen and radially arranged in the disc-ring m1 situated towards the outer periphery, for the purpose-of` increasing the sifting-effect.

For a better distribution of the sifted Inaterial falling down into the collecting receptacle or bunker L, scrapers a are for example arranged radially on the lower side of the plate-like screen, by which the sifted material fallen down into the collecting-receptacle or bunker 7L is distributed. If it is intended not to collect the sifted material in a receptacle or bunker, but to deliver it to any suitable place, a stationary bottom c can be provided below the rotatable plate-like screen, Fig. 5, and provided with an aperture w. Below said aperture lw is arranged an endless conveyor-band for supplying the material sifted through the plate-like screen by the scrapers u radially arranged on theV screen through the aperture fw of the bottom fu and onto the conveyor-bands In this manner the advantage is also obtained that the height of fall of the sifted material is limited as much as possible.

As shown in Figs. 4 and 6, a spouting device 1/ can be arranged at the outer periphery of the plate-like screen and situated Within the covering belt e in advance of the point of discharge of the material of larger grains in such a manner that a water-jet is thrown in an opposite direction to the rotation of the screen and against the material resting on the plate-like screen for the purpose of washing the sifted material before its delivery and of rinsing the material of larger grain not sifted together with the water through the slot-opening CZ at the periphery Aof the plate-like screen, whereby the material to be delivered is essentially improved.

What I claim is: l. A device of the character described comvprising, a screen, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots adjacent the upper. surface of the screen, a belt-pulley located outside the circumference of the screen, and a belt guided around said rim and said pulley, said belt being adapted to cover the slots in the rim throughout part of their rotation and to uncover said slots at another part.

2. A device of the character described coinprising, a screen, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outside the circumference of the screen, a belt guided around said rim and said pulley, said belt being adapted to cover the slots in the rim throughout part of their rotation and to uncover said slots at another part, an endless supply-band for delivering material tangentially onto the screen, and means for driving the said band.

3. A device of the character described comprising, a screen, said screen including a plurality of concentrically arranged disc-rings, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a beltpulleylocated outside the circumference of the screen, a belt guided around said rim and said pulley, an endless supply-band for delivering material tangentially onto the screen, and means for driving the said band at substantially the speed of the radial center of one of the said concentric disc-rings.

4. A device of the character described comprising, a screen, said screen including a plurality Of concentrically arranged disc-rings, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provi-ded with slots, a beltpulley located outside the circumference of the screen, a belt guided around said rim and said pulley, an endless supply-band for delivering material tangentiallyA ontoan inner disc-ring, and means for -driving theI said band at substantially the speed of the radial center of said inner disc-ring; u

5. A device of the character described comprising, a screen, said screen including a plurality of concentrically arranged disc-rings, meansfor rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided withv slots, a beltpulley located outside the circumference of the screen, a belt guided around said rim and said pulley, an endless supply-band for delivering material tangentially onto an inner disc-ring, anotherendless supply-band for delivering material tangentially' onto an outer disc-ring, and means for driving said bands respectively at substantially the speeds of the radial centers of said inner and outer disc-rings. n

6. A device of the character described comprising, a screen, means for rotating the screen about an axis inclined from the vertical, a rim projecting upwardly from the eriphery of said screen and being provi ed with slots, a belt-pulley located outside the circumference of the screen, and a belt guided around said rim and sai-d pulley.

7. A device of the character described comprising, a screen, means for rotating the screen, means for vibrating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outside thc circumference of the screen, and a belt guided around said rim and said pulley.

8. A device of the character described comprising, a screen, said screen including a plurality of concentrically arranged disc-rings, means for rotating the screen, means for vibrating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outside the circumference of the screen, and a belt guided around said rim and said pulley.

9. A device of the character described comprising, a screen, said screen having its upper surface somewhat dished in shape, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outside the circumference of the screen, and a belt guided around said rim and said pulley.

10. A device of the character described comprising, a screen, said screen including a plurality of concentrically arranged discrings, an inner disc-ring being provided with screenapertures concentrically disposed and an outer disc-ring being provided with screen-apertures radially disposed, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outsidethe circumference of the screen, and a belt guided around said rim and said pulley.

1l. A device of the character described comprising, a screen, means for rotating the screen, a rim projecting upwardly from the periphery of said screen and being provided with slots, a belt-pulley located outside the circumference of the screen, a belt guided around said rim and said pulley, and a water spouting device mounted adjacent the periphery of the screen and arranged to direct a stream of water upon the material being sifted and in a direction opposed to the direction of rotation of the screen.

In testimony, that I claim the foregoing as my invention, I have signed my name this 11th day of June 1928.

OTTO WIENCKE. 

